1. Field of the Invention
This invention generally relates to tools and, more specifically, to a tool for removing roofing shingles.
2. Description of the Prior Art
Normally, before a new roof can be installed on a building structure, the damaged roof is removed. When a shingle roof is replaced, the old shingles are normally discarded and replaced by new shingles. For this reason, it is normally desirable to remove the old shingles in the quickest, most convenient and most inexpensive way. Since such shingle removal is a labor intensive process, numerous shingle-removing tools have been devised for assisting a roofer in removing the old roof-covering materials.
The outer layers of a typical roof are formed of roofing shingles that are somewhat flexible and provided with a series of shingles that overlie, in staggered fashion, a lower course of like or similar shingles. Each portion of the roofing surface is thus covered by a plurality of layers formed, initially, by roofing felt or roofing paper and then by a first layer of shingles. In some instances, if a roof is re-shingled, a second layer of shingles is placed over the solid portion of the first shingles and over their flaps. When shingles become damaged, it is usually not possible to add a third layer of shingles since the strength of the roofing structure may not be able to support the weight of a third layer of shingles. It is therefore necessary to remove the shingles that are already on the roof, and this sometimes includes two layers of shingles.
The shingles are nailed to the roof with roofing nails that have wide, flat heads so that they can securely hold the soft shingle material. The nails are frequently invisible, as they are covered by the shingles to protect the nails from the elements. Thus, the nails retaining one course of shingles will be typically covered by the next course of shingles. Due to the manner in which such shingles are applied, it is not possible to merely raise one flap of a shingle to obtain access to the nails. The flaps frequently hide them, and it is difficult and inconvenient to obtain access to such nails. Removing shingles can be very a time-consuming and tedious task. While the shingles may be removed from the top down, that is, in the reverse order from the initial shingling of the roof, obtaining access to the nails and prying them up on a nail-by-nail basis, especially if two layers of shingles are to be removed, is extremely time-consuming and not customary in the field. Pry bars of various designs have been proposed, arranged to fit the neat layers of shingles or between the roof and layers of shingles so that a group of nails can be pried up from the roofing boards one at a time.
While numerous shingle removing tools have been proposed, such tools have suffered from various drawbacks in actual practice. Thus, for example, some such removal tools have not provided optimum leverage or mechanical advantage at the tip edge of the blade to quickly and conveniently remove shingles with an optimum amount of force and handle deflection or movement. Clearly, it is desirable to optimize the design of the tool to provide such leverage that it minimizes fatigue to the user. This is especially important when the shingles are to be removed from a large roof. When such leverage is not optimized, this can become a very physically demanding operation.
Also, such shingle or tile removal tools normally include a leading flat portion which is intended to be oriented substantially parallel to the surface on which the shingles or tiles are connected. However, the orientation of the leading edge of the head of the tool will be a function of a number of factors. Such factors include the angular orientation between the handle and the leading edge of the tool, the length of the handle and the height at which the user holds the handle in relation to the surface on which the tiles are mounted. The latter factor will also tend to be a function of how tall the user is, and whether the user holds the handle in a position that is most normal for the user during use, or whether the user is compelled to artificially raise or lower the tool during use, which can be an uncomfortable and tiring posture for the user. Since the orientation of the flat forward portion of the head of the tool is important to optimize the tool""s penetration beneath the tiles and to minimize friction forces on the tool itself, a properly designed tool can reduce fatigue and enhance removal efficiency.
Also, while most roofing nails are sufficiently short that they can be pulled by a roofing tool of the type under discussion, using normal manipulations of the tool, there are nails on occasion that are too long and the relatively short movements by the tool element that engages the nails are not sufficient to fully remove such nails. In these instances, a worker needs to carry a separate tool, such as a crowbar to remove such nails. This has complicated the work and made it less efficient.
Another problem that is frequently encountered with such tools is that most such tools frequently cause the shingles to climb up the blade and fall to the back of the blade. Such movements of the shingles make their removal more difficult and tedious, particularly when the shingles crack or break during removal, which further requires the handling of numerous additional sections of fragmented shingles. With prior art tools the fragments are propelled towards the worker, requiring separate collection of the fragments for disposal. Again, this makes the work more tedious and less efficient.
Accordingly, it is an object of the present invention to provide a tool for removing roofing shingles which does not exhibit the disadvantages inherent in prior art tools.
It is another object of the invention to provide a tool for removing roofing shingles which is simple in construction and economical to manufacture.
It is still another object of the invention to provide a tool as in the previous objects which is easy and convenient to use.
It is yet another object of the present invention to provide a tool of the type under discussion which can deflect removed shingles in the forward direction in which the tool is being moved to allow the shingles to be accumulated in a sweeping action for ultimate collection and disposal.
It is a further object of the invention to provide a tool as aforementioned which reduces sliding friction and efficiently converts the efforts by the user into forward and lifting motions.
It is still a further object of the invention to provide a tool for removing roofing shingles which can remove roofing nails typically used for securing the shingles to the roof, as well as for removing longer nails, the lengths of which are greater than the prying movements of the leading edge of the tool.
It is yet a further object of the invention to provide a tool for removing roofing shingles as aforesaid, which is ergonomic for use by most individuals, being dimensioned for optimum maneuverability by a person of average height.
It is yet another object of the invention to provide a removal tool as suggested in the previous objects which can quickly and conveniently remove both small and large roofing nails.
In order to achieve the above objects, as well as others which will become apparent hereinafter, a shingle removal tool in accordance with the present invention for removing shingles secured to a surface by means of nails, includes an elongate handle defining a handle axis and provided with gripping means at one axial end of the handle for facilitating the gripping of the handle by a user. A cutting head is generally aligned with such handle axis and has an upper end secured to the other axial end of said handle. A lower end of said cutting head is formed with a generally flat leading portion integrally connected to said upper end by means of an intermediary portion. Said flat leading portion defines a leading edge generally transverse to said handle axis and formed with a plurality of spaced-apart slots open at their leading edge and extending rearwardly of said leading edge and dimensioned and configured to receive and engage nails once said leading portion is in contact with and slides forwardly along said surface and engages secured shingles. Said leading and intermediary portions are angularly offset from each other to form a fulcrum edge generally parallel to the leading edge, as to orient said handle axis at a predetermined angle in relation to said surface when said flat leading portion lies flat on said surface. Said fulcrum edge serves to raise said leading edge above said surface by lowering the inclination of said handle below said predetermined angle to lift the shingles and/or nails in contact with said leading portion. Said intermediary portion is curved in a plane extending through said handle axis and normal to said flat leading portion to form a concave upper surface defining normal directions from said fulcrum edge to said upper end that increasingly approach the orientation of the plane of said flat leading portion.
In accordance with another feature of the invention, a nail-engaging means is provided on said intermediate portion spaced a predetermined height above said flat leading portion for engaging and removing nails, generally nails that are larger than nails intended to be removed by said flat leading portion, by lifting said handle about said fulcrum edge.
In accordance with still another object of the present invention, said flat leading and intermediate portions are dimensioned and configured so that said handle axis intersects said flat leading portion at a point substantially midway between said leading and fulcrum edges.
According to yet another feature of the present invention, said predetermined angle of said handle axis is selected to be within the range of 45xc2x0-55xc2x0 for dimensions between said fulcrum edge to said gripping means, generally along a direction normal to said surface, while said leading portion lies flat on said surface, within the range of 25 and 35 inches. In order to further enhance the efficiency in the use of the tool, in accordance with another feature of the invention, the ratio of the dimensions between said leading and fulcrum edges and said fulcrum edge to said gripping means, generally along said handle axis, is approximately within the range of 0.07 and 0.08.